The elements in the collection are returned in the order in which they would be encountered in a preorder traversal of the document tree. In a preorder traversal, the parent root node is visited first and each child node from left to right is then traversed.

The returned IXMLDOMNodeList object is live and immediately reflects changes to the nodes that appear in the list.

The getElementsByTagName method simulates the matching of the provided argument against the result of the tagName property of IXMLDOMElement. When executed, it does not recognize or support namespaces. Instead you should use the selectNodes method, which is faster in some cases and can support more complex searches.